Three of the major characteristics used to classify organisms are cell structure, mode of nutrition and cellularity. These characteristics help scientists determine how organisms are similar to each other as well as how they are different from each other.
Can I see the models?? I don´t know what the cactus looks like/
Answer:
Before the advent of modern biology, study of life and organism was in the realm of natural philosophy and was never in the club of classical sciences like physics, chemistry and engineering. Today biology is a science that studies life and living organisms.
Explanation:
A biologist can be categorized as a scientist because all the processes that supports scientific investigations are carried out in the study of biology- data collections, critical thinking, observation and collection of result for the purpose of public consumption.
On the other hand forensics is the mainly the aplication of science-mostly biology- in resolving criminal activities. It involves the collection of samples, anaylsing and presentaion of result for decison making.

<em><u>Nitrogen</u></em><em><u> </u></em><em><u>is</u></em><em><u> </u></em><em><u>not</u></em><em><u> </u></em><em><u>a</u></em><em><u> </u></em><em><u>product</u></em><em><u> </u></em><em><u>of</u></em><em><u> </u></em><em><u>photosynthesis</u></em>